The spatial microstructure exhibited by charge stabilized colloidal dispersion at very low ionic strength has been determined using static light scattering. The obtained structure factors have been analyzed assuming a DLVO type effective particle-particle interaction potential, and with the aid of the Ornstein-Zernike equation and the hyper-netted-chain closure. The effective charges needed to fit the experimental data in this way are found to be considerably smaller than the total number of ionizable groups on the surface. In order to account for this behavior, two approaches have been taken. Firstly, a widely used charge renormalization approach was applied. It is based on the idea that the potentials derived with linear approximations underestimate the actual charge characterizing the interaction. The surface charge does not seem to be an appropriate input parameter for this model. Secondly, electrophoretic mobilities were measured and converted into ζ-potential (using the O'Brien-White theory). The electrokinetic charges were also calculated. A discussion in terms of these electrokinetic data is presented. The similar behavior found between the effective and electrokinetic charges seems to point out that not only the renormalization has to be considered, but also the structure of the electric double layer.